In the making of hollow blown articles such as containers from plastic material, it has heretofore been suggested that labels be held in the cavity of mold sections by vacuum so that when a parison is blown outwardly into conformity with the cavity, the label becomes adhered or bonded to the article.
In one type of apparatus commonly known as an injection-blow apparatus, parisons in the form of tubes are extruded from an extruder into a neck mold of a head. The head includes label handling vacuum devices which remove labels from magazines and deposit the labels on cavities of mold sections.
One of the problems with such an arrangement is that a magazine is required for each of the label handling vacuum devices.
In another type of apparatus such as shown in U.S. Pat. No. 4,636,166, issued Jan. 13, 1987, intermediate endless belts are provided and indexed past magazines to pick up successively an array of labels and then label handling vacuum devices on the head remove the array of labels from the endless belts and deposit the labels in the cavities of the mold sections when the head moves down adjacent the extruder. Such an arrangement necessitates the use of intermediate belts with the associated costs and maintenance.
Accordingly, among the objectives of the present invention are to provide an in-mold labeling system which is more accurate, simpler, lower in cost and more reliable; which eliminates the use of endless belts and the associated label handling which applies the labels while the blow molding apparatus is performing other functions; and which requires only a single source of labels for each array of mold cavities.
In accordance with the invention, the apparatus for application of labels to the hollow blown plastic articles comprises a label carrier mounted for reciprocating movement between the open mold sections and supporting an array of spaced vacuum pick up devices. The carrier is mounted for reciprocating movement past a source of labels exterior to the blow molding mechanism so that labels are picked up by each of the vacuum devices and when the carrier is moved between the longitudinally spaced array of mold sections, the vacuum devices are actuated to deliver the array of labels to the cavities of the array of open mold sections at the same time as the take out mechanism is moved adjacent the mold sections to grasp the blown containers so that the labels are delivered with substantially no delay in cycle time.